Display screen or portion thereof with a transitional graphical user interface



FIG. 1 is a front view of a display screen or portion thereof with a transitional graphical user interface, showing our new design, illustrating a first image of the design, according to a first embodiment of the design.

FIG. 2 is an annotated front view of the design of FIG. 1, according to the first embodiment.

FIG. 3 is an enlarged front view of a portion of the design of FIG. 1, indicated by “A” in FIG. 2, according to the first embodiment.

FIG. 4 is a front view of a display screen or portion thereof with a transitional graphical user interface, illustrating a second image of the design, according to the first embodiment of the design.

FIG. 5 is an annotated front view of the design of FIG. 4, according to the first embodiment.

FIG. 6 is an enlarged front view of a portion of the design of FIG. 4, indicated by “B” in FIG. 5, according to the first embodiment.

FIG. 7 is a front view of a display screen or portion thereof with a transitional graphical user interface, showing our new design, illustrating a first image of the design, according to a second embodiment of the design.

FIG. 8 is an annotated front view of the design of FIG. 7, according to the second embodiment.

FIG. 9 is an enlarged front view of a portion of the design of FIG. 7, indicated by “A” in FIG. 8, according to the second embodiment.

FIG. 10 is a front view of a display screen or portion thereof with a transitional graphical user interface, illustrating a second image of the design, according to the second embodiment of the design.

FIG. 11 is an annotated front view of the design of FIG. 10, according to the second embodiment; and,

FIG. 12 is an enlarged front view of a portion of the design of FIG. 10, indicated by “B” in FIG. 11, according to the second embodiment.

The appearance of the transitional image sequentially transitions between the images shown in FIGS. 1 and 4 or between the images shown in FIGS. 7 and 10. The process or period in which any image transitions to another image forms no part of the claimed design.

Subject matter shown in broken lines is environmental and forms no part of the claimed design. 

CLAIM The ornamental design for a display screen or portion thereof with a transitional graphical user interface, as shown and described. 